The present invention relates to a tilt-latch for a pivotal sash window assembly and, more particularly to a tilt-latch mounted substantially flush in a top sash rail of a pivotal sash window.
A pivotal sash window adapted for installation in a master frame of a sash window assembly is well-known. The sash window assembly typically has opposed, vertically extending guide rails to enable vertical reciprocal sliding movement of the sash window in the master frame while cooperatively engaged with the guide rails. The sash window has a top sash rail, a base and a pair of stiles cooperatively connected together at adjacent extremities thereof to form a sash frame, usually a rectangular frame. Typically, a pair of spaced tilt-latches are installed on, or in, opposite ends of the top sash rail.
Each tilt-latch is generally comprised of a housing having an outward end opening and a latch bolt disposed within the housing. A spring disposed within the housing generally biases the latch bolt through the outward end opening to engage the guide rails of the master frame. The latch bolt has a control button to allow for actuation of the latch bolt. An operator can use his finger to engage the button and actuate the latch bolt wherein the latch bolt is retracted into the housing. This releases the latch bolt from the guide rail. When the latch bolts of the opposed tilt-latches are actuated simultaneously, the sash window can then be pivoted from the master frame.
A tilt-latch mounted in a top sash rail is typically called a flush-mount tilt-latch. An example of this type of tilt-latch is shown in U.S. Pat. No. 5,139,291, assigned to Ashland Products, Inc., the assignee of the present invention. To accommodate the flush-mount tilt-latch in the top rail, a slot is punched or routed in the top rail. Because material is removed from the top rail, the structural integrity of the top rail is decreased. The greater the length of the tilt-latch, the greater the amount of material that is required to be removed from the top rail, and thus, the greater effect on the structural integrity of the top rail.
As discussed, the window sash is fixed to the master frame by the nose of the latch bolt that engages the guide rail of the master frame. When wind forces act upon the window sash, a moment can be created about the point where the nose engages the guide rail. A moment arm associated with this moment corresponds to the length of the tilt-latch. The greater the length of the tilt-latch, the greater the moment that can be generated. This can possibly result in the latch bolt nose disengaging from the guide rail allowing the sash window to pivot uncontrollably from the master frame. Also, because holes have been punched into the top rail to accommodate the tilt-latches, a bowing of the top rail could occur under sufficient wind conditions. The wind forces may apply a twisting force on the tilt-latch in the top rail. Wind forces acting on the sash window may also apply torsional forces between the latch bolt and the housing.
The present invention is provided to solve these and other problems.
It is an object of the present invention to provide a tilt-latch adapted for releasably securing a pivotable sash window to a master frame of a sash window assembly.
The master frame has opposed, vertically extending guide rails. The sash window has a top sash rail, a base and a pair of stiles cooperatively connected together at adjacent extremities to form a frame. The top sash rail includes a pair of opposing header slots. Each of the header slots forms a pair of opposing, longitudinal header rails.
In accordance with one aspect of the invention, the tilt-latch has a housing adapted to be supported by the top rail. The housing has an outward end opening and an outer edge. A latch bolt is supported within the housing and has a nose adapted for engaging a respective one of the guide rails. The latch bolt moves past the outer edge of the housing when the latch bolt is retracted into the housing.
In accordance with another aspect of the invention, the tilt-latch has a housing adapted to be supported by the top rail. The housing has an outward end opening and a tongue extending from the housing. A latch bolt is disposed within the housing and has a nose adapted for engaging a respective one of the guide rails. The latch bolt has a channel that is in cooperative sliding engagement with the tongue.
According to another aspect of the invention, the tilt-latch further includes means for biasing the latch bolt through the outward end opening.
According to a further aspect of the invention, an actuator is connected to the latch bolt wherein the actuator can retract the latch bolt into the housing. If desired, the latch bolt could be designed to be actuated without requiring a separately connected actuator. An actuator could also be integrally molded with the latch bolt or attached separately.
According to another aspect of the invention, the tongue extends along a bottom wall of the housing and is spaced from sidewalls of the housing. The tongue preferably extends substantially along the entire length of the bottom wall of the housing.
According to a further aspect of the invention, the tongue has a flange extending transversely from the tongue and the latch bolt channel is in cooperative sliding engagement with the tongue and the flange.
According to yet a further aspect of the invention, the housing further includes a second tongue extending from a sidewall of the housing. The latch bolt has a second channel in cooperative sliding engagement with the second tongue.
According to another aspect of the invention, the housing further includes a cover and a pair of sidewalls depending from the cover. The cover has an elongated opening in communication with a peripheral opening. The elongated opening defines a pair of rails. The actuator has an actuator channel on opposed edges of the actuator that cooperate with the elongated opening rails wherein the actuator is slideable along the cover. A rear portion of the actuator slides through the peripheral opening. The latch bolt also has a post and the actuator has a notch. The post is received in the notch to connect the actuator to the latch bolt.
According to another aspect of the invention, the housing has an outer edge. The actuator or latch bolt moves past the outer edge of the housing when the latch bolt is retracted into the housing.
According to another aspect of the invention, the biasing means comprises a spring. The latch bolt has a spring surface and the spring has one end abutting the spring surface and another end abutting the housing. The tongue and the flange extending from the tongue substantially encapsulate a length of the spring.
Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.